Packaging method



Jan. 18, 1944. c. L. WAGNER PACKAGING METHOD Filed April 16, 1942 2 Sheets-Sheet 1 N Tm 0664,64 EV L Man/5e.

Jan. 18, 1944. C WAGNER 2,339,305

PACKAGING METHOD Filed April 16, 1942 2 Sheets-Sheet 2 C/mezir 4 Man/5e.

Patented Jam-l8, 1944 PACKAGING METHOD Charley L. Wagner, Menashs. Wis, assignor to Mills Company Rothschild,

Marathon Paper Wis, a corporation of Application April 16, 1242, Serial No. 429,285

I v Claims. (0!. 99-118) This invention relates to improvements in V the container are autogenously heat-sealed so as to provide a hermetically sealed package within which the foodstuff will be protected against loss of moisture and against contamination, mold growth, and other undesirable deterioration.

The type of package produced inaccordance with this invention-is similar to the one disclosed in patent to Palmer No. 2,274,344, February 24, 1942. The present method is designed to facilitate the production of this type of package by providing a prefolded container or wrapper so as to facilitate the manufacture of the package either manually or by automatic machinery.

Further details of the invention will be apparent from the accompanyin drawings wherein Figure 1 is a plan view of a blank from which the prefolded container is formed,

Figure 2 is a plan view illustrating the first step in forming the prefolded container,

Figure 3 is a plan view illustrating the final prefolded container,

Figure 4 is a fragmental perspective view showing the prefolded container in partially opened condition,

Flgure'5 is a similar view showing the container in more fully opened condition, I

Figure 6 is a fragmental perspective view showing the container fully opened up and retained within a receptacle, such as a wooden box, and

Figure 7 is a perspective view illustrating the completed package hermetically sealed.

Referring to the drawings. the prefolded container is formed from a suitable flexible sheet material 25, such as Cellophane (regenerated cellulose), Pliofilm (rubber hydrochloride) glassine, paper and the like, the sheet being coated on one side with a coating I! of a thermoplastlc' heat-sealable or pressure-scalable moistureproof composition such as a wax-rubber composition as disclosed in Abrams Patent n 2,054,113, September 15, 1938. any other as is then opened up to fit the receptacle either suitable type of pressure-scalable or heat-sealable composition may be utilised for the purpose of this invention. It is preferred to use a transparent sheet material as well as a transparent i or translucent thermoplastic coating so that the loads packaged in the container will be visible in the final package.

The blank 2! is cut to suitable sire and shape and the corners are preferably cut ofl diagonally as indicated at i2.

In forming the container, the blank is first folded'along the transverse medial line i, as illustrated in Figure 2, sothat the thermoplastic coating II is the inside of the folded blank. Heat or pressure or both are then applied by any suitable means to the marginal portions 2 so as to provide autogenously heat-sealed seams 2. Inasmuch as the coating ii at the margins is brought in face to face contact it will soften or suiliciently weld or coalesce to form an autogenously 8 8- strong and impervious seam, thereby forming a container having a closed bottom and an open top. The side portions of the container so formed are then folded inwardly along longitudinal lines 9 and II as wellasalonglines 4, 5,8,and l,soastoforma longitudinally extending re-entrant or gusset fold at each side of the container. As a result of such folding operation ear portions A will be formed as shown in Figure 4, which are adapted to be folded against the side portions of the container in the relation shown in F18- ure 4. If desired heat or pressure or both may beappiiedto the earportionAsoastosealthe entire area thereof.

The container so formed is preferably kept in flat folded condition as illustrated in Figure 3,

until it is to be used for forming a package of plastic foodstufl'. .The' final prefolded containers will have the appearance as illustrated in Figure 3, the gussets having a heat-sealed seam portions 2 folded inwardly as aportion of I the re-entrant folds as previously described.

ber of operations.

manually or by means of mechanical equipment so as to cause the container to assume the rectangular contour of the receptacle as illustrated in Figure 6, and to be in contact with the supporting wall portions of the receptacle.

The container will, after such openingopera-- tion, be given a square-bottom contour'and the tab portions A will assume the position as illustrated in Figure 6. wMolten cheese, or any other desired plastic foodstuff is then poured into the open receptacle so as to bring the foodstuff into direct contact with the coating l5 throughout. The pressure of the contents on the sides of the container will serve to press the walls of the container against the rigid walls of the wooden receptacle so that as the contents become set or hardened the container will have a smooth square-walled rectangular contour complemental to that of the interior contour. of the receptacle 20.

After the container has been filled, preferably about even or level with the top edges of the receptacle 20, the upper marginal portions lE-Ii of the side walls of the container are folded-inwardly toward each other over the top of the container contents. The marginal portions I! are brought into face to face contact and heat or pressure or both are then applied thereto to form an autogenously sealed scam I! as shown in Figure 7. During this operation, ear portions'B will be formed which may also be sealed throughout their area by heat or pressure or both, and

then folded upon the body of the package. A suitable cover may then be applied to the receptacle so as to complete same. During the formation of theupper seam as described, any

air inside the package is expelled so that a hermetically sealed package is provided.

The method of packaging herein disclosed is a distinct and important improvement of the procedures in forming a package as described in the Palmer Patent No. 2,274,344, or in the Abrams Patent No. 2,077,301, April 13, 1937. By utilizing prefolded containers, the number of steps required by the operator in forming the package is reduced to a minimum so that production of the packages is increased in a surprising manner. The prefolded containers are formed by suitable automatic equipment, and are supplied in flat prefolded condition ready to use. They can be readily inserted in the receptacle with a minimum loss of time and a minimum required num- The present packaging method therefore provides a distinct advance over the previous methods hitherto practiced.

It is obvious that changes and variations may be made in the packaging method herein described without departing from the spirit of the invention.

I claim:

1. The method of molding and wrapping a block of plastic cheese which comprises placing within a receptacle. a prefolded container formed from a single flexible sheet having a heat-sealable coating thereon, said sheet being folded upon itself to form a container having a closed bottom and open top with the coating on the interior thereof, each of the lateral margins of said folded sheet being autogenously heat-sealed.

in face to face relation by saidcoating on said sheet, said margins being folded inwardly to form longitudinally extending folds at each side of the folded container, opening said container and conforming the sides and bottom thereof to the contour of said receptacle, filling said con- 7| block ofp flcf dstuif tainer with plastic cheese while supported in said receptacle, autogenously heat-sealing the margins at the open end of said container in face to face relation by means of the coating on said wrapper and folding the extending portions of the wrapper pon the y ofv the package so formed.

2. The method of molding and wrapping a block of plastic cheese which comprises placing within a receptacle a prefolded container formed from a single flexible sheet having a heat-sealable coating thereon, said sheet being folded upon itself to form a container having a closed bottom and open top with the coating on the interior thereof, each of the lateral margins of said folded sheet being autogenously heat-sealed in face to face relation by said coating on said sheet, said margins being folded inwardly to form longitudinally extending gusset folds at each side of the folded container, opening said container and conforming the sides and bottom thereof to the contour of said receptacle, filling said container with plastic cheese while supported in said receptacle, autogenously heat-sealing the margins at the open end of said container in face to face relation by means of the coating on said wrapper and folding the extending porported in said receptacle,

age so formed.

3. The method of molding and wrapping a -bl0ck of plastic cheese which comprises placing within a receptacle a prefolded container formed from a single flexible transparent sheet having it V heat-scalable coating thereon, said sheet being folded upon itself to form a container having a closed bottom and top with the coating on the interior thereof, each of the lateral margins of 'said folded sheet being autogenously heatsealed in face to face relation by said coating on said sheet, said margins being folded inwardly to form longitudinally extending gusset folds at each side of the folded container, opening said container and conforming the sides and bottom thereof to the contour of said receptacle, filling said container with plastic cheese while supported in said receptacle, autogenously heatsealing the margins at the open end of said container in face to face relation by means of the coating on said wrapper and folding the extend-- ing portions of the wrapper upon the body of the package so formed.

4. The method of molding and wrapp g a block of plastic foodstuff which comprises placing within a receptacle a prefolded container formed from a single flexible sheet having a pressureand heat-sealable coating thereon, said sheet being folded upon itself to form a container having a. closed bottom and open top with the coating on the interior thereof, each of the lateral margins of said folded sheet being autogenously sealed in face to face relation by said coating on said sheet, said margins being folded inwardly to form longitudinallyextending folds at each side of the folded container, opening said container and conforming the sides and bottom thereof to the contour of said receptacle, filling said container with plastic material while supautogenously sealing themargins at the open end of said container in face to face relation by means of the coating on said wrapper and folding the extending pertions of the wrapper upon the bodyof the package so formed.

5. The method of molding and wrapp ng I which comprises placin: within 9, receptacle 1 prefoided-contninerl hlner formed from, '1; single sheet fliezcct having a thermoplastic 'coatin: thereoxnscid in: said contain sheet being folded won-itpeiito form containmin said receptacleut lcmlm l heathaving a closed bottom and ton with 5 at the ope -end oi eaid'concoatinxon the interior thereof, each of the'int 'in i to nice rehtion by" m0! the erai margins oi and folded sheet being nutop flnz'on said mpil 'meatseeiinzend ioidi'n: enously bent-sealed in face to face i portions 0! the, upon the v said coating on said sheet, said margins being oi tne-packuello iormed. j folded inwardiyio form gusset folds stench- 0 1 Q side'oi' the folded container, opening aaidcml OHARLIYL. Wm 

